What is absent menstruation?

Absent menstruation, or Amenorrhea, is the absence of menstrual bleeding. It happens when a girl hasn’t had her first menstrual Period by age 16. It also occurs then a woman fails to menstruate for 3 to 6 months.

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Amenorrhea can happen for many reasons. The most common cause is pregnancy. However, amenorrhea may also be caused by various lifestyle factors, including body weight and exercise levels. In some cases, hormonal imbalances or problems with the reproductive organs might be the cause.

You should see your doctor if you’re experiencing amenorrhea. The underlying cause of your missed periods may require treatment.

Types of absent menstruation

The two types of amenorrhea are referred to as primary and secondary.

Primary amenorrhea is when a teenage girl has reached or passed the age of 16 and still hasn’t had her first period. Most girls begin menstruating between ages 9 and 18, but 12 is the average age. Secondary amenorrhea is when a woman has stopped menstruating for at least three months. This is the more common form of amenorrhea.

In most cases, both types can be treated effectively.

Causes of absent menstruation

Primary and secondary amenorrhea can occur for numerous reasons. Some causes are natural, while others are medical conditions that need to be treated.

Natural causes most likely to cause amenorrhea include pregnancy, breast-feeding, and menopause.

Lifestyle factors may include excessive exercise and stress. Also, having too little body fat or too much body fat may also delay or stop menstruation.

Hormonal imbalancesmay cause amenorrhea. They are usually triggered by tumors on the pituitary gland or the thyroid gland. Low estrogen levels or high testosterone levelscan also cause them.

Medications can cause amenorrhea in some women. Antipsychotics and antidepressantsare often involved. Chemotherapydrugs and medications that treat high blood pressurecan cause problems with menstruation as well. Suddenly stopping birth control pills may also lead to several months of absent periods before the cycle returns to normal.

Physical defects such as structural problems in the female reproductive organsmight be responsible for absent or delayed menstruation. These issues can result from birth defects, tumors, or infections that occurred in the womb or shortly after birth. In rare cases, missed periods could be a symptom of Asherman’s syndrome. This occurs due to scarring in the uterus after surgery, which can prevent mestruation.

Genetic disorders or chromosomal disorders, such as Turner syndromeand Sawyer syndrome, can sometimes cause late menstruation.

When to see a doctor about absent menstruation

A teenage girl who hasn’t started her periods by at least age 16 should see a doctor. A trip to the doctor’s office is also necessary if she is age 14 or older and hasn’t experienced any signs of puberty yet. These changes would include the following in numbered order of appearance:

thelarche (breast bud development)

pubarche (pubic hair development)

menarche (onset of menstrual periods)

Menstruating women and teens should see their doctor if they have missed three or more periods in a row.

What to expect at a doctor’s appointment

When you see your doctor about amenorrhea, your doctor will perform a physical exam and ask you a series of questions. Be prepared to talk about your normal menstrual cycle, your lifestyle, and any other symptoms you’re experiencing. Your doctor will also order a pregnancy test if you haven’t had a period in three months. If that condition is ruled out, you may need more tests to determine the underlying cause of your missed periods. These diagnostic tests may include:

Blood tests, which will allow your doctor to check hormone levels in your body. Prolactin, luteinizing hormone, and follicle stimulating hormoneare all related to menstruation. Determining these levels can help your doctor determine or rule out the cause of your absent periods.

Ultrasoundis an imaging test that uses high frequency sound waves to create detailed pictures of the inside of your body. It enables your doctor to view various organs, such as the ovaries and uterus, and check for abnormal growths.

CT scanis another type of imaging test that uses computers and rotating X-ray machines to create cross-sectional images of the body. These images allow your doctor to look for masses and tumors in your glands and organs.

Treatment for absent menstruation

Treatment for amenorrhea varies depending on the underlying cause. Hormonal imbalances can be treated with supplemental or synthetic hormones, which can help normalize hormone levels. Your doctor may also want to remove ovarian cysts, scar tissue, or uterine lesions that are causing you to miss your menstrual periods.

Your doctor may also recommend making simple lifestyle changes if your weight or exercise routine is contributing to your condition. Ask your doctor to refer you to a nutritionist or dietician, if necessary. These specialists can teach you how to manage your weight and physical activity in a healthy way.

Having no menstrual periods is called amenorrhea.

Amenorrhea is normal in the following circumstances:

Before puberty

During pregnancy

While breastfeeding

After menopause

At other times, it may be the first symptom of a serious disorder.

Amenorrhea may be accompanied by other symptoms, depending on the cause. For example, women may develop masculine characteristics (virilization), such as excess body hair (hirsutism), a deepened voice, and increased muscle size. They may have headaches, vision problems, or a decreased sex drive. They may have difficulty becoming pregnant.

In most women with amenorrhea, the ovaries do not release an egg. Such women cannot become pregnant.

If amenorrhea lasts a long time, problems similar to those associated with menopause may develop. They include hot flashes, vaginal dryness, decreased bone density (osteoporosis), and an increased risk of heart and blood vessel disorders. Such problems occur because in women who have amenorrhea, the estrogenlevel is low.

Absent menstrual periods – primary

Absence of a woman’s monthly menstrual

period is called amenorrhea.

Primary amenorrhea is when a girl has

not yet started her monthly periods, and

Has gone through other normal changes that occur during puberty Is older than 15

Alternative Names

Causes

Most girls begin their periods between ages 9 and 18. The average is around 12

years old. If no periods have occurred when a girl is older than 15, further testing may be needed.

The need is more urgent if she has gone through other normal

changes that occur during puberty. Being born with incompletely formed

genital or pelvic organs can lead to a lack of menstrual periods.

Some of these defects include:

Blockages or narrowing of the cervix

Hymen that has no opening

Missing uterus or vagina

Vaginal septum (a wall that divides the vagina into 2 sections)

Hormones play a big role in a woman’s menstrual cycle. Hormone problems can occur when:

Changes occur to the parts of the brain where hormones that help manage the menstrual cycle are produced.

The ovaries are not working correctly.

Either of these problems may be due to:

Anorexia (loss of appetite)

Chronic or long-term illnesses, such as cystic fibrosis or heart disease

Genetic defects or disorders

Infections that occur in the womb or after birth

Other birth defects

Poor nutrition

Tumors

In many cases, the cause of primary amenorrhea is not known.

Symptoms

A female with amenorrhea will have no menstrual flow. She may have other signs of puberty.

Exams and Tests

The health care provider will perform a physical exam to check for birth defects of the vagina or uterus.

The provider will ask questions about:

Your medical history

Medicines and supplements you may be taking

How much exercise you do

Your eating habits

A pregnancy test will be done.

Blood tests to measure different hormone levels may include:

Estradiol

FSH

LH

Prolactin

17 hydroxyprogesterone

Serum progresterone

Serum testosterone level

TSH

T3 and T4

Other tests that may be done include:

Chromosome or genetic testing

Head CT scan or head MRI scan to look for brain tumors

Pelvic ultrasound to look for birth defects

What Is Absent Menstrual Periods?

Treatment

Treatment depends on the cause of the missing period. Lack of periods that is caused by birth defects may require hormone medicines, surgery, or both.

If the amenorrhea is caused by a tumor in the brain:

Medicines may shrink certain types of tumors.

Surgery to remove the tumor may also be needed.

Radiation therapy is usually only done when other treatments have not worked.

If the problem is caused by a bodywide disease, treatment of the disease may allow menstruation to begin.

If the cause is the bulimia, anorexia or too much exercise, periods will often begin when the weight returns to normal or the exercise level is decreased.

If the amenorrhea cannot be corrected, hormone medicines can sometimes be used. Medicines can help the woman feel more like her friends and female family members. They can also protect the bones from becoming too thin (osteoporosis).

Absent or irregular periods

Menstrual cycle disorders can cause a woman’s periods to be absent or infrequent. Although some women do not mind missing their menstrual period, these changes should always be discussed with a health care provider because they can signal underlying medical conditions and potentially have long-term health consequences. A woman who misses more than three menstrual periods (either consecutively or over the course of a year) should see a health care provider.

Amenorrhea — Amenorrhea refers to the absence of menstrual periods, and is classified as either:

Primary (when menstrual periods have not started by age 15 years)

Secondary (when menstrual periods are absent for more than three to six months in a woman who previously had periods)

Oligomenorrhea — Oligomenorrhea is the medical term for infrequent menstrual periods (fewer than six to eight periods per year).

The causes, evaluation, and treatment of amenorrhea and oligomenorrhea are similar and will be discussed together.

Causes Of irregular Periods

The brain (including the hypothalamus and pituitary gland), ovaries, and uterus normally follow a sequence of events once per month that helps to prepare the body for pregnancy (figure 1). Two hormones, follicle-stimulating hormone (FSH) and luteinizing hormone (LH), are made by the pituitary gland. Two other hormones, progesterone and estrogen, are made by the ovaries.

Menstrual cycle disorders can result from conditions that affect the hypothalamus, pituitary gland, ovaries, uterus, cervix, or vagina.

Primary amenorrhea — Some of the more common causes of primary amenorrhea include the following:

Conditions that are present at birth but may not be noticed until puberty. These conditions include genetic or chromosomal abnormalities and abnormalities of the reproductive organs (eg, if the uterus is not present or developed abnormally).

All of the conditions that lead to secondary amenorrhea can also cause primary amenorrhea.

Secondary amenorrhea — Pregnancy is the most common of secondary amenorrhea. Other common causes include the following:

Hypothalamic amenorrhea. This occurs when the hypothalamus slows or stops releasing gonadotropin-releasing hormone (GnRH), a hormone that influences when a woman has a menstrual period.

Hypothalamic amenorrhea is associated with low body weight (defined as weighing 10 percent below ideal body weight) (calculator 1 and calculator 2), a low percentage of body fat, eating disorders such as anorexia nervosa or bulimia nervosa, emotional stress, strenuous exercise, and some medical conditions or illnesses. However, in some cases, there is no obvious explanation for hypothalamic amenorrhea.

Prolactin-secreting pituitary tumors are another common cause of secondary amenorrhea. (See “Patient education: High prolactin levels and prolactinomas (Beyond the Basics)”.)

Oligomenorrhea — Many of the conditions that cause primary or secondary amenorrhea can also cause a woman to ovulate irregularly (oligomenorrhea). However, most women who develop infrequent periods have PCOS. (See ‘Polycystic ovary syndrome’ below.)

Evaluation Of Irregular Periods

The evaluation of amenorrhea/oligomenorrhea includes a complete medical history and physical examination.

History — There are often clues about the cause of amenorrhea in a woman’s personal and family medical history. A woman should mention if she had any health problems during infancy or childhood, when her first period started (if there was a first period) and how frequently periods have occurred since. If known, the woman should also mention if there is any family history of irregular menstrual periods.

Other important points include the presence of discharge from the breasts, hot flashes, adult acne, facial or chest hair, and headaches or impaired vision. The clinician will also ask about any medications, herbs, and vitamins used; recent stress; recent gynecologic procedures; changes in weight, diet, or exercise patterns; and illnesses.

Physical examination — During the physical examination, the provider will examine the face, neck, breasts, and abdomen. A pelvic examination will also be performed.

Testing — Depending upon the individual, the clinician may order blood tests. Because pregnancy is the most common cause of secondary amenorrhea, a pregnancy test is usually recommended for women whose menstrual periods have stopped. Blood tests to measure hormone levels will also be ordered.

In selected cases, a magnetic resonance imaging (MRI) test may be done to determine if there are hypothalamic or pituitary gland abnormalities in the brain (figure 2). Occasionally, in women with a suspected chromosomal abnormality, a chromosome analysis may be recommended. A pelvic ultrasound may be recommended to identify abnormalities of the uterus, cervix, and vagina.

Treatment Of Irregular Periods

The goal of treatment is to correct the underlying condition. For a woman who is trying to become pregnant, restoring fertility may be another goal. (See “Patient education: Ovulation induction with clomiphene (Beyond the Basics)” and “Patient education: Infertility treatment with gonadotropins (Beyond the Basics)”.)

Hypothalamic amenorrhea — Women with hypothalamic amenorrhea are sometimes able to resume normal menstrual periods after making certain lifestyle changes, such as eating a higher-calorie diet, gaining weight, reducing the intensity or frequency of exercise, and reducing emotional stress.

Low body weight and/or nutritional deficiencies – Women with eating disorders such as anorexia nervosa or bulimia often need specialized care. This usually includes nutrition counseling and work with eating disorder specialists.

Strenuous exercise – Although exercise offers many health benefits, exercising frequently or excessively can lead to amenorrhea. Studies suggest that amenorrhea develops when a woman’s caloric intake is less than she burns with exercise and other daily activities. Most women with amenorrhea associated with exercise have also lost weight (resulting in a weight less than 90 percent of the ideal body weight) (calculator 1and calculator 2).

For women with exercise-associated amenorrhea, treatments include increasing calorie intake and reducing the frequency and/or intensity of exercise. These measures are particularly important if a woman is trying to become pregnant. All women with amenorrhea should be sure to consume 1200 to 1500 mg of calcium daily (or take a calcium supplement) and a vitamin D supplement (400 international units daily). (See “Patient education: Calcium and vitamin D for bone health (Beyond the Basics)”.)

Some clinicians recommend estrogen and progestin hormone replacement (or a hormonal contraceptive, such as a birth control pill) for women with hypothalamic amenorrhea. These treatments can reduce the risk of developing osteoporosis later in life. (See “Patient education: Hormonal methods of birth control (Beyond the Basics)” and “Patient education: Osteoporosis prevention and treatment (Beyond the Basics)”.)

Ovarian failure — Normally, a woman stops ovulating around the age of 50 years; this is called menopause. If a woman stops ovulating before age 40 years, this is called premature ovarian failure (or primary ovarian insufficiency). (See “Patient education: Early menopause (primary ovarian insufficiency) (Beyond the Basics)”.)

Being diagnosed with ovarian failure is usually unexpected and can be distressing, especially if the woman has not completed childbearing. In these situations, counseling with a social worker or psychotherapist may be of benefit. With most types of ovarian failure, pregnancy can be achieved using injectable fertility medications and donor eggs. (See “Oocyte donation for assisted reproduction”.)

Although ovarian failure cannot be cured, hormone therapy (HT) with estrogen and progesterone (or a hormonal contraceptive, such as a birth control pill) can help prevent or treat many of the symptoms and long-term consequences of menopause, such as hot flashes, vaginal dryness, and osteoporosis. HT has risks of its own in older women. However, a young (20- to 50-year-old) woman who takes HT does not have the same risks as a ≥50-year-old woman who takes HT. Current practice is to provide HT for women with premature ovarian failure until age 50 years, the average age of menopause.

High prolactin — Women with amenorrhea and hyperprolactinemia can usually have normal menstrual periods and become pregnant when treated with medications called dopamine agonists (bromocriptine and cabergoline are examples). This is discussed in detail separately. (See “Patient education: High prolactin levels and prolactinomas (Beyond the Basics)”.)

However, women with these conditions can have menstrual periods and become pregnant when treated with injectable fertility medications. (See “Patient education: Infertility treatment with gonadotropins (Beyond the Basics)”.)

Endometrial adhesions (Asherman syndrome) — Some gynecologic procedures, such as a dilatation and curettage (D and C), can cause adhesions (a type of scar tissue), which damage the uterine lining. If adhesions are extensive, menstrual blood loss will be reduced or absent. A clinician may recommend surgery to remove the scarred tissue, followed by estrogen treatment to stimulate regrowth of the lining. (See “Patient education: Dilation and curettage (D and C) (Beyond the Basics)”.)

Anatomic problems — Surgery is often an effective treatment if amenorrhea is caused by a blockage in the reproductive tract. (See “Diagnosis and management of congenital anomalies of the vagina”.)

What are the causes of missed periods?

The medical word for absent periods is ‘amenorrhoea’. If you have never had a period, this is called primary amenorrhoea. If you were having regular periods which have stopped, this is called secondary amenorrhoea. There are many possible causes for both primary and secondary amenorrhoea. Most causes can account for either type.

Often there is nothing to worry about when periods stop, and no serious cause. There are certain times when it is normal not to have periods. These include:

Before puberty. Girls start to develop from around the age of 9 years and their periods start a year or two later. Up until that point girls do not have periods.

During pregnancy. If you are pregnant, your periods will normally stop until after the baby is born.

During breast-feeding. If you are fully breast-feeding, you will normally not have a period until you stop. You may find you have a bleed if you drop a feed, or start to breast-feed much less.

After menopause. The menopause is the time in your life when your ovaries stop producing eggs and you stop having periods. The average menopause is around the age of 51. See separate leaflet called Dealing with the Menopause for more details.

If you are using certain types of contraception. Some types of contraception may stop periods. They do not do so in all women; however, it is normal not to have periods (or to have very light periods) if you are using:

The progestogen-only contraceptive pill (POP, or mini-pill).

The intrauterine system (IUS) – sometimes called a coil.

A progestogen contraceptive injection.

Stress

Stress affects the chemical messengers called hormones which are released from your brain. These hormones then go on to affect other hormones released from your ovaries which normally trigger your periods. Stress or a sudden shock can stop your periods in this way. Usually if this is the case, they resume naturally over some time.

Low body weight

Losing weight may result in periods stopping. This can occur if your body mass index (BMI) goes below 19. If you have an eating disorder called anorexia nervosa, losing too much weight can result in your periods stopping. It may also happen to athletes, gymnasts, long-distance runners and people who do an excessive amount of exercise.

Polycystic ovary syndrome (PCOS)

PCOS is a common condition which can cause periods to be very infrequent or sometimes stop altogether. Women with PCOS may have other symptoms such as difficulty losing weight, spots (acne) and too much body hair. See separate leaflet called Polycystic Ovary Syndrome for more details.

Hormone problems

A number of conditions which affect hormone levels may cause periods to stop. This includes:

A condition where a hormone called prolactin is too high. This is called hyperprolactinaemia. The most common cause of this is a non-cancerous (benign) growth in the brain called a prolactinoma.

Conditions affecting a gland in your neck called the thyroid gland. The thyroid gland produces hormones which may affect periods. If you are producing either too much hormone (hyperthyroidism) or too little (hypothyroidism), your periods may be affected.

Congenital adrenal hyperplasia. This is a rare inherited condition where steroid hormones of the adrenal glands are not produced normally. There are different forms of this condition but some can lead to absent or infrequent periods.

Another disorder of the steroid hormones, called Cushing’s syndrome.

Inherited problems

In rare cases, abnormal genes can be a cause of not having periods. In most of these, there will be primary amenorrhoea (ie periods never start). One example of this is Turner syndrome. In this condition, girls tend to be short, have particular features and have ovaries which do not work properly. They often do not start periods when other girls of their age do. See the separate leaflet called Turner Syndrome for more details.

Other inherited (genetic) conditions may cause differences in genitals and female organs. For example, in a condition called androgen resistance syndrome, the child has female genitals outside but no female organs on the inside. With no ovaries or womb (uterus), these children will not have periods.

Occasionally babies do not develop normally in the womb before birth and may be born with problems which will prevent periods. For example, rarely a girl may be born without a vagina, or with a blockage in the vagina. Sometimes the first time this is apparent is when she does not start to have periods as expected.

Early menopause

The average time for women’s periods to stop is at the age of 51. However, there is quite a wide range. If periods stop before the age of 40, this is very early and is said to be premature menopause. Periods stop and there are usually other symptoms of menopause such as hot flushes.

Medicines and medical treatment

As discussed above, a number of contraceptive treatments can stop you having periods. Other medicines can affect periods too. Examples are some medicines for schizophrenia (antipsychotic medicines), an anti-sickness medicine called metoclopramide and strong painkillers called opiates.

A number of operations may result in absent periods. For example, after a hysterectomy you will not have periods. A hysterectomy is an operation where the womb is removed. As the blood during a period comes from the womb, you will never have periods again afterwards. Another operation (called endometrial ablation), which is sometimes done for heavy periods, also causes periods to stop. In this operation the lining of the womb is removed. This is not usually permanent and periods start again in time.

Treatments for cancer, such as radiotherapy or chemotherapy, can also damage the ovaries and result in absent periods. Recreational drugs such as heroin may also cause periods to stop.

Getting back to normal after stopping contraception

When you have been on the combined oral contraceptive (COC) pill or an injection form of contraception, it can take a while for your periods to restart once you stop the contraception. It can take a few months for your body’s own cycle to restart and it can take several months before you have a period.

What should I do if I have not started my periods?

Girls start their periods at a very variable age. So it may be that your friends have been having periods for a while but you have not. Usually this will be normal variation and nothing to worry about. Ask your doctor’s advice if:

You are 16 years old or older and still have no periods.

You are 14 years old or older and have not developed breasts or pubic hair and do not have periods.

You have a pain in your tummy every month but no bleeding.

You can feel a lump in the lower part of your tummy.

You have had sex without using contraception (ie if there is any chance you could be pregnant).

You have lost weight or have symptoms of anorexia nervosa. (See separate leaflet called Anorexia Nervosa for more details.)

You feel unwell in yourself in any other way.

What should I do if I have had periods which have now stopped?

Don’t panic! In most cases there is nothing serious going on. The most important thing to do is to do a pregnancy test if there is any chance at all you could be pregnant. If you otherwise feel well in yourself, and you are not pregnant, then the chances are your periods will start up again in due course.

You should see a doctor if:

You have not had a period for three months and your periods were previously regular.

You have not had a period for nine months but your periods have always been infrequent.

You could be pregnant.

You wish to become pregnant.

You have hot flushes and are under the age of 45.

You have lost weight or your BMI is 19 or less.

You or someone close to you is concerned about your eating or weight.

You have milk leaking from your breasts and are not breast-feeding.

You feel unwell in yourself (for example, headaches, changes in your vision, have lost or gained weight).

You have not had a period for six months after stopping the contraceptive pill. (Or 12 months after the last contraceptive injection.)

You are worried about your lack of periods.

Will I need any tests?

If you go to see a doctor about your periods stopping, first of all the doctor will ask you some questions. For example, the doctor will want to know:

If you have ever had periods and whether they were regular.

How long you have not had periods for.

If you have recently been using any contraception.

If you are on any medication or have any other medical conditions.

If you have recently lost weight.

If you are under any stress.

If there is any chance you could be pregnant.

If you have any other symptoms, such as hot flushes or milk leaking from your breasts. (Hot flushes may suggest an early menopause; milk leaking from your breasts suggests high levels of the hormone prolactin, discussed above.) The doctor may also ask about symptoms of pregnancy such as morning sickness or tender breasts.

Your doctor may then wish to examine you. The doctor may want to check your weight and height and then work out your BMI. They may also want to feel your tummy. They may want to look for signs of possible causes. (For example, excess body hair suggesting PCOS, or a lump in the neck suggesting a problem with the thyroid gland.) In some cases an internal examination may be needed.

Whether further tests are needed will depend on what has been discovered from talking to you and examining you. You may not need any tests at all. Tests which may be needed include:

A pregnancy test (usually checked from a sample of urine).

Blood tests. These are done to check out a number of possible causes. They may be done to check hormone levels (such as thyroid hormones and prolactin as discussed above, or the levels of hormones coming from the ovary). Occasionally tests for gene abnormalities may be needed.

An ultrasound scan. (This may be needed to check your internal organs are normal, especially if you and your doctor wish to avoid an internal examination. This might be the case, for example, in young girls who have not started their periods.)

How are absent periods treated?

This depends on the cause. In many cases no treatment is needed. See the specific leaflets about the various causes for information on how each is treated.

Are there any complications of missed periods?

In the short term, there are no complications of missing a few periods. However, if it goes on for a longer time, it may cause some problems.

Infertility

Women who are not having periods may not be producing eggs from their ovaries (ovulating). This would mean they would not be able to become pregnant naturally. For some women this may be an issue. However, for many causes, there is a treatment to help with this, so discuss it with your doctor if you want to become pregnant. See the separate leaflet called Infertility for more details.

Weak bones (osteoporosis)

When the absent periods are combined with low levels of the female hormone oestrogen, there may be a risk of bones weakening. Oestrogen helps keep bones strong, and they start to weaken after menopause. If they become excessively weak and break (fracture) easily, this is called osteoporosis. This only applies to women who have not had a period for a long time (a year or more). It is particularly a risk for women whose periods have stopped due to early menopause, weight loss, anorexia nervosa or excessive exercise.

Heart disease

It is suspected that low oestrogen levels also put a woman at risk of heart disease. Also women with PCOS are more likely to develop risk factors for heart disease, such as high blood pressure, high cholesterol levels, and diabetes. A healthy diet is particularly important for women with PCOS to reduce the risk.

Irregular periods

Other patterns of periods which are different to normal may also occur, as follows.

Infrequent periods

Having periods less often than normal is called oligomenorrhoea. The causes of this are much the same as the causes of absent periods discussed above. The most common cause is PCOS.

Erratic periods

For some women, periods don’t happen regularly but seem to come at unexpected times. Some months the gap between periods may be shorter than 28 days and other months it may be longer. This is common in teenage girls starting their periods and may go on for a few years as hormones settle down. It is also common in women as they approach the menopause. Often no cause is found and doctors put it down to a condition called ‘dysfunctional uterine bleeding’. This means no abnormality has been found to account for it and there is nothing to worry about. If bleeding is heavy, or the erratic cycle is a problem, there are treatments which can help, so see your doctor.

Bleeding between periods

There are many causes for bleeding between periods. It is common in the first 2-3 months after starting the combined oral contraceptive (COC) pill.

Outlook (Prognosis)

The outlook depends on the cause of the amenorrhea and whether it can be corrected with treatment or lifestyle changes.

Periods are not likely to start on their own if the amenorrhea was caused by one of the following conditions:

Birth defects of the female organs

Craniopharyngioma (a tumor near the pituitary gland at the base of the brain)

Cystic fibrosis

Genetic disorders

You may have emotional distress because you feel different from friends or family. Or you may worry that you might not be able to have children.

When to Contact a Medical Professional

Call your provider if your daughter is older than 15 and has not yet begun menstruating, or if she is 14 and shows no other signs of puberty.

Hormones and menstruation

Menstrual periods are regulated by a complex hormonal system. Each month, this system produces hormones in a certain sequence to prepare the body, particularly the uterus, for pregnancy. When this system works normally and there is no pregnancy, the sequence ends with the uterus shedding its lining, producing a menstrual period. The hormones are produced by the following:

The hypothalamus (part of the brain that helps control the pituitary gland)

The pituitary gland, which produces luteinizing hormone and follicle-stimulating hormone

The ovaries, which produce estrogen andprogesterone

Other hormones, such as thyroid hormones and prolactin (produced by the pituitary gland), can affect the menstrual cycle.

The most common reason for no menstrual periods is

Malfunction of any part of this hormonal system

Less commonly, the hormonal system is functioning normally, but another problem prevents periods from occurring. For example, menstrual bleeding may not occur because the uterus is scarred or because a birth defect, fibroid, or polyp blocks the flow of menstrual blood out of the vagina.

High levels of prolactin, which stimulates the breasts to produce milk, can result in no periods.